The forward threader failed to check whether it can actually duplicate
blocks. The following adds this in a similar place the backwards threader
performs this check.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR tree-optimization/106422
* tree-ssa-threadupdate.cc (fwd_jt_path_registry::update_cfg):
Check whether we can copy thread blocks and cancel the thread if not.
* gcc.dg/torture/pr106422.c: New testcase.
---
gcc/testsuite/gcc.dg/torture/pr106422.c | 14 ++
gcc/tree-ssa-threadupdate.cc| 4 +++-
2 files changed, 17 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/torture/pr106422.c
diff --git a/gcc/testsuite/gcc.dg/torture/pr106422.c
b/gcc/testsuite/gcc.dg/torture/pr106422.c
new file mode 100644
index 000..a2cef1aecb6
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr106422.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+
+void vfork() __attribute__((__leaf__));
+void semanage_reload_policy(char *arg, void cb(void))
+{
+ if (!arg)
+{
+ cb();
+ return;
+}
+ vfork();
+ if (arg)
+__builtin_free(arg);
+}
diff --git a/gcc/tree-ssa-threadupdate.cc b/gcc/tree-ssa-threadupdate.cc
index f901c7759e3..0f2b319d44a 100644
--- a/gcc/tree-ssa-threadupdate.cc
+++ b/gcc/tree-ssa-threadupdate.cc
@@ -2678,7 +2678,9 @@ fwd_jt_path_registry::update_cfg (bool
may_peel_loop_headers)
for (j = 0; j < path->length (); j++)
{
edge e = (*path)[j]->e;
- if (m_removed_edges->find_slot (e, NO_INSERT))
+ if (m_removed_edges->find_slot (e, NO_INSERT)
+ || ((*path)[j]->type == EDGE_COPY_SRC_BLOCK
+ && !can_duplicate_block_p (e->src)))
break;
}
--
2.35.3